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Feel the intensity, not your equipment. Maximum image quality. Minimum weight. The new ZEISS SFL, up to 30% less weight than comparable competitors.

Anyone have any ideas what this is? (1 Viewer)

I agree with Bill above. The spots are too well distributed and uniform in size to be a fungus.

My experience is fungus is more patchy and larger and uneven, like a spider web.

I would just use the binoculars, it may not get any worse, and yes it can be cleaned up by a
qualified tech. Nikon should cover this under their warranty, I would check there first.

Good luck.


I am thinking of sending the pics to Nikon to see if they can shed some light on this but as the bins are out of their 10 year warranty it would most likely be very costly to get them fixed. At least they are now just a back up pair.


"Experientia Docet”
United States
I took a much closer look at my Ultravid lenses. The problem is on the focusing lens and it appears to be coating failure in both oculars. I'll have Leica address it and get back with the results.


Staff member
Anyone know if the focusing mechanism (which is grease based on these) is open to the internal optics?

Hi from Sheffield.
I would rule out any kind of 'contamination' spreading from a point inside the binos. The distribution of the spots is so uniform across the lens it shows no signs at all of radiating out from an internal source. And the shape of the spots is uniformly point-like with no hint of elongation or smear. It looks to me like a coating defect and if it is it would need lens replacement. If you come down Sheffield way I have loupes and we could meet to investigate further.

Good luck

I took a much closer look at my Ultravid lenses. The problem is on the focusing lens and it appears to be coating failure in both oculars. I'll have Leica address it and get back with the results.

I would be very interested in their findings.

For now, I have sent my images to Nikon customer support and are waiting to here back. Will keep you informed.
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Seconded. Best 10x loupe I've ever had.

Also useful to check if that little dark speck on your arm is a piece of dirt or a tick.


That loupe does have good reviews. On the very rare occasions when I am in the field and want to see something very close up like insects or tiny flowers etc I have always used my bins reversed. Tried to use this same technique on the spots on my Nikons but can't get the right angle or lighting.

Lol, I have had loads of ticks over the years. They are usually big enough to see and I can usually spot them down to about 1/2mm in size. Surprising how wide spread these are in the UK.


Well-known member
Single small coating spots/faults are common and may be due to a speck of dust on the glass before coating takes place.

Some high end lenses have to be coated immediately they are made (polished). If not the glass rapidly degrades. This is usually with exotic high refractive index glass, which is used in these optics costing $10,000 or more each.
It is the coating that protects the glass underneath.

I think that there are only two likely causes of the Nikon lens problem here. Coating fault or miniscule droplets.

Early 1960s and late 1950s Minolta and Canon lenses had great problems with grease volatilising and coating the iris blades. These lenses usually had seized up irises, which had to be cleaned, Lenses were simpler then and more easily dismantled. By the late 1960s these problems were solved with new greases.

I think that all TTH professional lenses were made with disassembly and cleaning in mind.

I was given a Zeiss 75cm f/6.3 Telikon lens that was sitting in English's optics skip in Essex. It had almost the whole front element deeply gouged out by metal girders in the skip.
On testing visually with an eyepiece I was amazed to see the original superb Zeiss quality show through, but with terrible loss of contrast. These were survey lenses of the highest quality for 30cm square format.

If the Nikon binocular looks good with normal use, then it isn't worth spending money on it.
Although I would probably not use it except as a car back up binocular just for emotional reasons rather than logic.


Well-known member
I suppose it doesn't pay to look into these things but I've looked into my 8x32 FL eyepieces again. The left is clear as a bell. The right looks like a petri dish full of flu virus. I have no idea what the heck is going on.

I guess that's partly why I just get a Swaro. No probs, and they know how to fix it.

I was debating about the new 8x30 CL. Not so much anymore. I'll buy it.



Well-known member
A good description of fungus.
Zeiss might fix it F.O.C. but may be not. It needs cleaning. I hope not yet etched into coatings or glass.
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